Plait claims that the diatoms Wickramasinghe found, "a type of algae, microscopic plant life," are simply a freshwater species found on Earth. Wickramasinghe doesn’t deny that the meteorite sample his team studied contains freshwater diatoms.

"But — there are also at least half a dozen species that diatom experts have not been able to identify," Wickramasinghe said.

Boom, we’re done. That is an open admission that his sample is contaminated. It doesn’t matter that some portion of his sample is unidentifiable — and most likely, it’s the stuff he calls ‘filaments’ and ‘red rain cells’ that aren’t even biological … he cannot claim that the only possible source of that material is outer space.

And then there’s this vague bit:

Critics have also asserted that the meteorite in question may not, in fact, be from outer space. Could it simply be an Earth rock?

According to Wickramasinghe, "This was also the guess of the Sri Lankan geologists who first looked at the rock. They had considered the possibility that the rock may be … a rock that was struck by lightning. We examined this possibility and found it to be untenable. From all the evidence we possess (and we are planning to publish this), I personally have no doubt whatsoever that this was a stone that fell from the skies."

So the expert geologists tell him it’s a terrestrial rock, and then declares on the basis of unpublished evidence that he won’t describe that it can’t be. Right. I’m unconvinced. It doesn’t even matter if it is a meteorite or not at this point — it’s contaminated, and he published it as if it were not.

Surely, even if you could find a meteorite with fossilized diatoms in it, and could prove there were no contamination, the odds would be overwhelming that the rock originated on Earth. There have certainly been impact events energetic enough to hurl debris into a near-Earth heliocentric orbit.

There have certainly been impact events energetic enough to hurl debris into a near-Earth heliocentric orbit.

Most orbits deriving from collision events with Earth are heliocentric, unsurprisingly, if they’re not actually limited to being geocentric. We’ve only found a handful of meteorites which have fallen inwards from Mars; far fewer rocks from Earth will ever have made it out to Mars.

But still. This is, sadly, another case of a once-respected scientist who has gone completely off the deep end.

They had considered the possibility that the rock may be … a rock that was struck by lightning. We examined this possibility and found it to be untenable. They had considered the possibility that the rock may be … a rock that was struck by lightning. We examined this possibility and found it to be untenable.

Here’s a thought: Rather than using the pseudoscientists’ false dilemma, why don’t you demonstrate that it’s a meteorite, not simply assuming it because you ruled out (quite possibly incorrectly) a terrestrial scenario or two?

Does every crackpot rely upon an illegitimate default to their favorite junk? It would seem so.

Ok, full justification for ruling out a terrestrial sourcing of the rock isn’t ready for publication, fine. Couldn’t we have gotten a brief overview of the highlights?

And given that there is solid proof of contamination if it is a meteorite- where is the information on the tests done to sort out terrestrial contamination from what the thing carried with it? At least he claimed tests were done regarding the meteorite issue, he didn’t even hint that they did anything other than “we don’t know therefore space” regarding the fossils.

Though it is HuffPo. This guy looks like a crackpot, but HuffPo science coverage tends to be bad enough that I wouldn’t be surprised if he actually adressed these concerns in his response to them, and they just didn’t see the relevance or thought their readers were too dumb to understand.

He could have pointed out that what was referred to in the reply was probably meant to be a fulgaritehttp://en.wikipedia.org/wiki/Fulgarite, which is actually a lot more likely than it being a meteorite.

But the claim that it is a carbonaceous chondrite has one implication that was missed which heaps another helping of implausibility on top of all the others. First of all it would be realatively easy to offer conclusive evidence that it in fact is a CC – a petrographic thin section photomicrograph at low magnification under polarized light and anyone with competence in optical mineralogy could identify it at least tentatively. They are very distinctive critters. But the good part comes last. Carbonaceious chondrites a fascinating for their petrology and structure. Back in the day (~ 1978) when last I worked on meteorites at all the mostly widely accepted hypothesis for how CCs (like Allende) formed was as condensates from a zone of the early solar nebula. They are very old. In fact they tend to support the estimates of the age of the formation of the solar system, greater than about 4.3 billion years. The zone of the nebula in which they formed was moreover hot enough to melt most elements, but not the carbon matrix, hence the formation of the chondrules (spherical liquid droplets that then crystallized into a variety of common and not so common minerals) by being incorporated into the carbon in a micro-gravity environment. So such meteorites were never part of a body large enough to have enough gravity, to have an atmosphere and thus afford the possibility of free water at the surface. In fact most of the minerals present in the chondrules would have long since have been chemically weathered to alteration products in the presence of any water.

So the claim that it is a carbonaceous chondrite leads to two possibilites: a) it isn’t and therefore is not
a meteorite at all or b) that it is and it plopped itself down in a nice warm pond full of living diatoms that found their way into the fairly porous matrix of the rock. I think a) is the most likely because I agree with Plait that it doesn’t look at all meteoritic (ablation crust anyone?). There is a third possibility of course which might fit with Louis’ bit of snark above but I wouldn’t want to make any accusations.

BTW – to get the scanning electron images of the diatoms the sample would have had to have been prepared extensively, more extensively than to just make a simple petrographic thin section, so where are all the pretty mircographs in polarized light that would provide conclusive evidence that it is a meteorite at all?

One more BTW – what is Chandra Wickramasinghe’s primary area of expertise? Astro-biology?

I’d like to say that this is the first time in more than 6 years of semi-lurking on Pharyngula I have actually known something about a topic under discussion that might not have been apparent to most others.

Thank you! If it’s a chondrite, it didn’t come from a planet. Case closed on that front. He’s going to have to claim, then prove, that this rock is a non-terrestrial planetary meteorite. He has about two choices (one, really). These would be fairly readily identifiable.

“This is, sadly, another case of a once-respected scientist who has gone completely off the deep end.”

Once respected by whom? Wickramasinghe has a long history of crackpottery (his
PhD is in mathematics and his doctorate in science is honorary). 1. The SARS virus
is from an extraterrestrial source. 2. The universe has always existed rather than
being about 13.8B years old. 3. Evolution can’t produce more complex life forms
from simpler ones, all species descended from other species that were at least
as complex as them. 4. In McLean vs Arkansas he testified in favor of creationism
and specifically against evolution having occurred. Of course his credibility at the
trial was compromised somewhat by exposing his claim that insects were actually
smarter than people, but they were concealing this from humanity. 5. He has also
claimed that the best Archaeopteryx fossil is merely a clever forgery. In short, he
suffers from a profound level of scientific illiteracy combined with a reciprocal ego.

From all the evidence we possess (and we are planning to publish this)…

But why wasn’t it published to begin with? If this “evidence” forms the entire basis for saying that the rock is even of extraterrestrial origin in the first place, it seems to me it might be sorta relevant. What kind of moron would leave that out of the original article?

This does raise the question of what observation WOULD increase the likelihood that we’re looking at something that didn’t evolve on Earth. Say you find some microscopically interesting-looking goop on a meteor sample. (Not unrealistic that they wouldn’t all be cooked – C. elegans survived the Columbia crash.) If it has DNA, if it’s not related how do you know what primers to use? I guess you could run it through a column and look for interesting compounds. Even if you do find something novel, how do we know we just didn’t isolate some weird new cyanophyte from the parking lot where the meteor landed?

The best indication would be material with isotopic signatures (carbon-13/carbon-12; oxygen-16/-17/-18; etc) that match nothing on Earth. This is how we distinguish the source bodies of different sorts of meteorites from one another, and how we can identify ~100 nm-across interstellar dust grains embedded in much larger masses of solar-system material.

Wickramasinghe does not have such evidence. I can say that definitively because it takes longer than 3 weeks to do such an analysis, and because any lab with the hardware to do so would look at Wickramasinghe’s nonsense and refuse to waste time on something so silly (unless there was something otherwise interesting about the rock/diatoms concerned).

Even if you do find something novel, how do we know we just didn’t isolate some weird new cyanophyte from the parking lot where the meteor landed?

We don’t. Indeed, we can’t even be sure that something isn’t of extraterrestrial origin, just because it’s identical to a terrestrial species. Certainty is irrelevant. We have to look for the most parsimonious explanation.
With that in mind, what we would want is something that shows significant differences from normal terrestrial life. Once we find that, we go looking for that type specifically in our immediate environment. After a decade of not finding it, we might consider the conclusion that it’s extra-terrestrial.

My point is that such a conclusion isn’t reached from one data point at one instant. If you’re going to support a conclusion as revolutionary as that, you have to prepare yourself for the long haul. You have to accept that, no matter how solid your evidence is, nobody is going to accept it until they’ve had the chance to go over it with a fine-tooth comb.

Once respected by whom? Wickramasinghe has a long history of crackpottery (his PhD is in mathematics and his doctorate in science is honorary). 1. The SARS virus is from an extraterrestrial source.

Straight from Fred Hoyle’s claim that the universe is full of viruses and bacteria.

2. The universe has always existed rather than being about 13.8B years old.

When Hoyle & Wickramasinghe proposed the steady-state theory, it was a respectable explanation for the expanding universe. But then the data about the microwave background came in.

5. He has also claimed that the best Archaeopteryx fossil is merely a clever forgery.

Yeah, that was deeply embarrassing for Hoyle and him, or anyway it should have been. The “Piltdown chicken” was a direct consequence of their idea that “macroevolution” is caused, and only caused, by viruses from space upsetting all genomes, so a Mesozoic bird would be impossible. They didn’t know shit about the preparation of fossils, they evidently didn’t know how many specimens of Archaeopteryx were known, and they evidently had no fucking clue about any other Mesozoic birds, never mind that Ichthyornis and Hesperornis and Enaliornis had been known for a hundred years and Baptornis, Parahesperornis and a bunch of fossil feathers* and a lot of footprints for quite some time as well.

* Isolated feathers may or may not come from birds; but surely the appearance of feathers counts as “macroevolution” and led them to consider old Archie a forgery in the first place?

If it has DNA, if it’s not related how do you know what primers to use?

Use very short random ones and see what happens.

That said, I don’t see a reason to expect DNA in life that, in Spock’s words, “spawned in a different ocean”. There are just too many alternatives.

I guess you could run it through a column and look for interesting compounds. Even if you do find something novel, how do we know we just didn’t isolate some weird new cyanophyte from the parking lot where the meteor landed?

Cyanobacteria are well known, including their chemical makeup and their genome. Recognizing a cyanobacterium as such isn’t difficult.

“When Hoyle & Wickramasinghe proposed the steady-state theory, it was a respectable explanation for the expanding universe. But then the data about the microwave background came in.”

I was well aware of that, and my list was brief and lacking much detail. Hoyle and
Wickramasinghe continued to hang on to the stady state universe model long after
it had been invalidated. In fact, Hoyle held onto it until he died. I don’t know his
current thoughts on the matter, since he no longer has any (or at least refuses to
publish them). Wickramasinghe, on the other hand, is still swinging wildly at the
imaginary dragons in his head (commonly known as tilting at windmills). Sadly, the
Hymenoptera have him totally outclassed in the critical thinking department.

“Comparison of the SEM images of another fossil diatom in the Polonnaruwa meteorite with a
modern diatom Sellaphora blackfordensis (Mann, 1989,1999) is shown in Fig 7 and leaves
scarcely any room to doubt the identity of the former. Again we stress that contamination is
decisively ruled out because the structure in the meteorite is deemed to be a fossilised object,
and fossils diatoms were not present near the surface of the Earth to contaminate a new fall of
meteorites. “

…fossils diatoms were not present near the surface of the Earth to contaminate a new fall of
meteorites.

How do they know that? Looking through the article, the only reference I can find about where the “meteorite” was found is a large map of Sri Lanka with a vague star on it and the following text:

“…a large meteorite disintegrated and fell in the village of Araganwila, which is located a few miles away from the historic ancient city of Polonnaruwa.”

No description of where exactly it was found, what the local terrain was like, what condition it was in. They don’t even mention exactly who found it. Under these conditions how could they possibly rule out contamination?

The objective here SHOULD be to keep an open mind. Not buy the claim outright. Not deny the claim outright. But keep an open mind to any and all possibilities.

The problem in achieving this is that we are no longer an open minded society. Our culture has produced a generation of self-proclaimed experts in nearly every segment. Right off the bat, all one has to do is take a picture of a squirrel jumping between the camera and the subject and immediately you see proclamations of fakery from every photoshop ‘desk’pert on the web.

Denial is not an avenue to understanding nor is it the be-all and end-all of any subject… but it is what we do best here in the opening decades of the 21st century.

The objective here SHOULD be to keep an open mind. Not buy the claim outright. Not deny the claim outright. But keep an open mind to any and all possibilities.

And to judge those possibilities according to the evidence. That bit is somewhat important too.

The fact remains that this is sloppy work for an under-grad student, much less for a serious paper that’s drawing quite controversial conclusions. For crying out loud, the guy says they have evidence that the rock came from space, but he didn’t mention that in the paper? They don’t mention where the rock was found; they rule out contamination based on… I’m not quite sure what; they completely gloss over the fact that some of the diatoms found are identical to species found on earth, which should be a big hint that there’s something very wrong; they take all this and then draw a completely irresponsible, broad-sweeping conclusion.

And of course, there’s the crowning glory; publishing in a two-bit “journal” with no peer review. If they were really serious about doing science, they’d put their work out for the community to evaluate. Instead, they’re trying to shield their pet theory from any critique.